Method of trimming and subdividing plaster-board



1. SCHUMACHER. METHOD 0F TRIMMING AND SUBDIVIDIANG PLASTER BOARD. APPLICATION FILED .IULY I9, i920.

1,358,340. Patented Nov. 9, 1920.'

2 SHEETS-SHEET I.

J. SCHUMA'CHER.

METHOD 0F TBIMMING AND SUBDIVIDING PLASTER BOARD.

' APPLICATION msn :uLv 19,1920.

1,358,340, mm1 Nov. 9,1920.

2 SHEETS-SHEET 2.

UNI'rl-:D*` gs'rifxTlairs PArlx-:NT-oi-#F1CE JOHNVSCHUMACHER, 0F rLOS AGELES, CALIFORNIA.

METHOD or TRIMMING AND sUBDivIDING MASTER-BOARD.

To V'all whom ft'may concern.' l z Be it known that I, JOHN SCHUMAGHER, a

lcitizen of the United States, and residing at i `Los Angeles, in the 4county of, Los Angeles -and State ofCalifornia, have invented new and A useful Improvements in Methods of Trimming and Subdividing Plaster-Board, of which the following is a specification. i Y

This invention'relates to a method of sub-y dividing and trimming plaster board and es-v pecially to the steps before actual severing of the board.V

In 4alwell known method of making plaster board, initial lengths of the green board are piled or stacked on .trays in their moist and plastic condition, in which position-v the yplaster is allowed to harden or set. After the plaster has set, the 'lengths are subdivided and trimmed 'by passing the tray with the plaster board stacked thereon under a circular saw. In order to sever all `.of the sheets of board in the stack, especially the bottom` y sheet, the' saw edge must pass slightly below the under surface of the bottom sheet. This requires kerfs in the tray at the lines of severance, or the kerfs are formed by the saw cutting into the trays surface. In either event the tray eventually has kerfs in its surface. The result is that the sheet of. green plaster board first rlaid on the ytray and being the bottom piece sags into the kerfs and sets withprominences on its under surface, which destroys the value of this piece, and the bottom one not, being e perfectly flat isapt to cause the upper ones to be hardened'with irregular surfaces. This y invention is associated with such a process i for making plaster board, and the primary object thereof is to provide steps in the process whereby a fiat surface without furrows,

kerfs, 'or prominences is provided for the stack of plaster board to rest on in its green f condition and remainwhile the plaster sets thus producing perfectly flat sheets; there'- after to dispose the plaster board without ydisturbing the stacked relation so that it `may be severed upon a surface having kerfs corresponding to the linesof severance.

These objectsare accomplished by the instrumentalities shown in the'accompanying drawings, and by means of which my improvedprocessfvmay be carriedA nut.- How- Specication of Letters Patent.

Patented Nov. 9,1920.

Application filed J'uly k19, 1920. Serial No. 397,199.

ever, the means'shown is not the only means by'which my process can be effected.

Figure 1 1s a` sideelevation of a car withV stack holding mechanism thereon; Fig. 2 is a Side view ofthe cuttin tray; Fi .'3 is an l end elevation on an en arged sca e of the structure with a stack of plaster board clamped therein; Fig. 4 is a fragmentary sidev view showing details of the clamping mechanism for the rings; Fig. 5 is a perspective view of thesetting tray; Fig. 6 is a perspective view of the cutting tray; Fig.

7 is an enlarged fragmentary-sectional View through the cutting tray and a stack of plaster board showing they saw `cutting the board; and Fig. 8 is a transverse sectional view showing the sawtrimming an edge of the stack.

Referring more particularly lto Figs. 1 'y and 3, a frame supported upon wheels riding u ontracksfis indicated by A. The device or holding a stack of plaster board is indicated generally by B, andthe stack of plaster board is indicated by C. A leveling frame is indicated generally by D.

The frame Ais rectlngular, and at each l end thereof are a pair of channel irons 9 spaced from one another. lOvare mounted upon the irons and journaled therein are wheels 11. These wheels support semi-circular sections 12 of angle form. Secured to the sections 12 are bars 13 to support theflower tray. -For each semicircular section 12 there isa corresponding semi-circular section 14 to complete the ring. Secured to semi-circular section 14 is a bar 15 for supporting the cutting tray.y Each pair of sections 12 and 14 forms a split ring. To provide for securing the sections of a ring to each other, hooks 16 are mounted on the sections k14 adjacent slight offset provided with a pivot pin 21.V

On the endof link 19 is a pivot pin 22. A lever 23 is mounted upon the pivot pins 21 and 22. When the links 18 and 19 are placed over their respective hooks, the ,lever 23,

Bearing blocks f vtraywith the plaster hoard referring to Fig. 3, should be in un per posi* tion. To lock the split ring set gether, lever 23 is sivuini d Fig. 5, is formed of Lbeams u vwl oli is mounted any suitable ii" norting member indicated by T15. The t. tray construction are not impr that the uppej surface o? .vithout iurrows or character and is ber 25 niav be sec Y any oit the Well lmovvr ents.

The cutting tr covered by striL s surte/rc. These strips are another to torni hei ifs outer e` are ot the which the plaster hoard is to L The over all dimensions oi this preferably less tl .n that ot the The leveling trame D compases pivotally mounted upon the sid frame i and pivotally secured at t to a frame 29 adapted to be dis". osed neath the setting tray. Secured to one the links 2S is a lever The extends across the trarne il and sim 28 are mounted upon the opposi ot' trarne A. Thus, the t' swung upwardly by lever parallel movement. lt e. side oit the tray and levels the lao The car holding position to receive green plaster board as i plaster board forming d vicesn tray is placed upon the bars 'l-- 12 and thc tray is leveled by in leveling frame D. The green plaster board is stacked thereon, and when the C has been completed, it is allowed or harden. The severing'tray is then nlaco jl on the top ot' the stack as shown in lfig. Sections lll are then placed in position l clamped to the sections l2 by means o links 18 and 19. The plaster board hat' initially hardened is not affected bv clamping. r Jiter setting, the lcv l D is lowered and the stack inverte is easily accomplished as the ste ride upon the Wheels ll. liter hasbeen inverted, sections clamped from sections ll, the and setting tray removed,

ferred to position for subdivision a f ming, As the plaster boardv setk l.

it has not the softness Which would cause the portions of the sheet next to the tray to sag into the kerfs or over the edges et the tray. The sheet which was nent to the settling tray has during the setting process rested noon a smooth sur'face and hardened per f' lj] hat.

.Referring particularly to Figs. i and B, a t'ragment of a frame Si carrying a circular aw 82 is shovvn for subdividing and trimmin g the board. In Fig. 7, the saw is shown disposed in position ior subdividing the hoard into commercial sizes. lt .vill be noted that the saiv enters the keri's 2S, thereby cleanly severing the entire stack ot board. ln Fig. 8, the saw is shown trim ming the edges of the boarifl.

lt is obvious that l have provided a method, whereby every sheet ot the stach will harden with smooth surfaces and nf sheet is lost or damaged.

Alllh at I claim in :m

l. The method oi severing plaster hoard, which consists in disposing moist plastic lboard upon a support having a smi'ioth un interrupted surface, permitting setting oit the plaster, placing a support having surtace with saw kert's thereover, inverting the board so that it will rest on the support having the kerfs, removing the support having the smooth surface, and severing the board at said kerfs.

F2. The method of severing plaster board, which consists in disposinginitial lengths oit plaster board in superficial contact in a :nach upon a support having a smooth sur- :tr e, permitting setting ot the board, aite.' `the board has set placing a support on saifil s wack, inverting said stack so that it will. rest on the last mentioned support, removing the lirst mentioned support, and severing the board.

3. The method oit severing plaster board, which consists in disposing green hoard in a stack between supports, the lower support having a smoth uninterrupted surface and the upper support having urroWs for a saw.j allowing the plaster board to set While on the smooth surface, inverting the stack after the board is set so that it rests on the support having the furrows, removing the support having the smooth surface, and severing th`J board at said furroWs.

et. The method ot severing plaster board, which consists in disposing green hoard in stack upon a support having a smooth unin terrupted surface, allowing the setting ot the plaster, placing thereover a support having a surface not in contact therewith at the desired lines of severance, clamping said supports to each other, inverting the stack after the board is set so that it rests on the last mentioned support, removing the irst mentioned support, and severing the board.

5. The method of severing plaster board, which consists in disposing green board in 'Hifi clamping sai a stack upon a support having a smooth un-v interrupted surface, allowng thefsetting of the plaster, lacingl thereover a support,

d) supports to each other, invertngy thestack after the board s set so that it rests on the last mentioned support,

removing the support having the smooth surface andsevering the board at said furj rows. p

In witness that I claim the foregoing I 10 have hereunto subscribed my name this 8th day of July, 1920.

JOHN SCHUMACHER. 

